Abstract: A fixing apparatus fixes a toner image on a recording material by conveying and heating the recording material at a nip portion, and includes a first rotating member, a second rotating member configured to form the nip portion with the first rotating member, the first and second rotating members being arranged such that rotation of the second rotating member causes rotation of the first rotating member, a frame configured to support the second rotating member, so as to be rotatable and an opening and closing part arranged to open and close relative to the frame on the downstream side of the nip portion in the conveyance direction of the recoding material, the opening and closing part having a duct through which air flows.

Abstract: An image forming apparatus for forming a toner image on a recording material has an image forming unit configured to form the toner image on the recording material; a fixing unit configured to fix the toner image on the recording material while heating and conveying the recording material bearing the toner image at a nip portion, the fixing unit including a heating rotation member and a roller forming the nip portion with the heating rotation member; and a voltage applying unit configured to apply a potential difference between a surface of the heating rotation member and a surface of the roller, wherein a plurality of print modes different in conveyance speed of the recording material at the nip portion are carried out, and wherein the voltage applying unit applies the potential difference smaller in a first print mode than the potential difference in a second print mode.

Abstract: A fixing device includes first and second members, a frame supporting the second member, and two pressure mechanisms provided on either end of the first member. The mechanism includes a lever having one end supported by the frame in a rotatable manner in a pressure direction, and a helical compression spring disposed between a first spring support provided on the other end of the lever and a second spring support on the frame. At least one of the first and second spring supports includes a first area and a second area closer to the spring in the axial direction than the first area, the first area is in contact with an area of the spring close to a winding end of the spring, and the second area is in contact with an area of the spring farther away from the winding end in a winding direction than the first area.

Abstract: A fixing device includes: a cylindrical film; a nip forming member; and a back-up member for forming a nip. The nip forming member includes a projected portion. A projection amount of the projected portion is smaller in an end portion region positioned at an end portion of the projected portion with respect to a generatrix direction of the film than in a central region positioned at a central portion of the projected portion with respect to the generatrix direction, at least a part of the end portion region being inside a feeding region of a maximum-sized recording material usable in the fixing device. With respect to the recording material feeding direction, a width of the part, of the projected portion, inside the nip is broader in the end portion region than in the central region.

Abstract: A roller used for a fixing apparatus has: a core; a first elastic layer that is formed outside the core and includes a first tapered portion on an edge of the roller in an axis direction; and a second elastic layer that is formed outside the first elastic layer and includes a second tapered portion on the edge in the axis direction on the same side as the first elastic layer, the second elastic layer having hardness that is higher than hardness of the first elastic layer. A second start point, which is a start point of the second tapered portion, is set in a position closer to the center of the roller in the axis direction than a first start point, which is a start point of the first tapered portion.

Abstract: A fixing device includes: a cylindrical film; a nip forming member; and a back-up member for forming a nip. The nip forming member includes a projected portion. The projection amount of the projected portion is smaller in an end portion region positioned at an end portion of the projected portion with respect to a generatrix direction of the film than in a central region positioned at a central portion of the projected portion with respect to the generatrix direction, at least a part of the end portion region being inside a feeding region of a maximum-sized recording material usable in the fixing device. With respect to the recording material feeding direction, the width of the part of the projected portion inside the nip is broader in the end portion region than in the central region.

Abstract: A fixing device includes: a cylindrical film; a nip forming member; and a back-up member for forming a nip. The nip forming member includes a projected portion. A projection amount of the projected portion is smaller in an end portion region positioned at an end portion of the projected portion with respect to a generatrix direction of the film than in a central region positioned at a central portion of the projected portion with respect to the generatrix direction, at least a part of the end portion region being inside a feeding region of a maximum-sized recording material usable in the fixing device. With respect to the recording material feeding direction, a width of the part, of the projected portion, inside the nip is broader in the end portion region than in the central region.

Abstract: An image forming apparatus includes: a fixing portion for heat-fixing the image on a recording material; a duct including a suction port for sucking air from an outside of the image forming apparatus and an exhaust port for delivering the air to the outside of the image forming apparatus; and a fan for forming a flow of the air from the suction port toward the exhaust port in the duct. The duct includes a merging portion, between the suction port and the exhaust port, for merging the air from the neighborhood of the fixing portion with the flow of the air by taking the air from the neighborhood of the fixing portion inside the duct. The recording material on which the image is fixed at the fixing portion is cooled by the air delivering through the exhaust port.

Abstract: An image forming apparatus includes a toner carrying roller for carrying a toner, an image carrying member, contacting the toner on the toner carrying roller, on which a toner image is to be formed with the toner, and an electrode portion provided at an opposing position in which the electrode portion opposes the toner carrying roller via the image carrying member interposed therebetween. The toner image is formed on the image carrying member by changing a value of a voltage, on the basis of image information, applied to the electrode portion, and the toner carried on the toner carrying roller and the image carrying member contact each other in a toner contact area. The toner is moved between the toner carrying roller and the image carrying member in a toner movement area by changing the value of the voltage applied to the electrode portion, and the toner movement area is present downstream of the toner contact area with respect to a movement direction of the image carrying member.

Abstract: An image forming apparatus includes: an image bearing member configured to bear a toner image; a plurality of electrode portions; a control unit configured to control a voltage applied to the electrode unit based on image information; and a toner bearing member configured to bear toner and form a toner image on the image bearing member according to the voltage applied to the electrode portion, in which ?>1.22 is satisfied and rx?/ry? is defined as ?, where Dy indicates a thickness of the image bearing member, Dx indicates a distance between the electrode portions adjacent to each other, rx? indicates a resistance component of the image bearing member in a direction parallel to Dx and ry? indicates a resistance component of the image bearing member in a direction parallel to Dy in a rectangular solid body including Dx and Dy in a side.

Abstract: An image forming apparatus includes a toner carrying member for carrying a toner; an image carrying member, contacting the toner on the toner carrying member, on which a toner image is to be formed with the toner; and an electrode portion provided at an opposing position in which the electrode portion opposes the toner carrying member via the image carrying member interposed therebetween. The toner image is formed on the image carrying member by changing a value of a voltage, on the basis of image information, applied to the electrode portion. The toner carried on the toner carrying member and the image carrying member contact each other in a toner contact area. The toner is moved between the toner carrying member and the image carrying member in a toner movement area by changing the value of the voltage applied to the electrode portion. The toner movement area is present downstream of the toner contact area with respect to a movement direction of the image carrying member.